There's a good chance there is. I'd have to profile the different parts though to see what's taking it so long though. Unfortunately, I don't have an HDD attached to my development machine at the moment. Certain portions of the load code can easily be sped up, but others cannot without EXTREMELY significant changes.

Edit: I tried running it off a flash drive, and it still only took a second because of filesystem caching. Looks like I'll need some more details on your setup. Are you using your own build, or one of the nighties? What OS is this on? How much RAM do you have? Approximately how many mods do you have installed within the data directories specified in openmw.cfg? Approximately how many .bsa's? Are you working with multiple cells open (if so how many) or just a preview?

Are you using your own build, or one of the nighties? What OS is this on? How much RAM do you have? Approximately how many mods do you have installed within the data directories specified in openmw.cfg? Approximately how many .bsa's? Are you working with multiple cells open (if so how many) or just a preview?

It takes the same amount of time to reload in a completelly new game project (created in CS). The lists of meshes, textures, sounds, videos etc. are still populated with Morrowind's assets though, even in a new .omwgame.

In both cases, file indexing takes the longest. I wonder if the nightlies are debug builds? I guess I'll download one and check.

Edit: Nightlies are release builds. I'm not sure why it takes so much longer on your computer. Based on what you mentioned, it shouldn't be taking 6 seconds. I'm assuming that the issue is file indexing, because that fits both with what you mentioned and my own testing. This should only be an issue if you have tons of files in the data folders being scanned, or many added bsa's. Can you check the terminal to make sure those are the only 3 bsa's being added?

Not sure if related, but starting CS anew takes 13 seconds from the Open dialogue to getting the editor window ready. I also removed OpenMW and Morrowing along with data folders and installed anew, but with no changes.

starting CS anew takes 13 seconds from the Open dialogue to getting the editor window ready.

Yes that's related. That's when the index is initially built.

If your willing, it would be nice of you could run a build with the reload profiling. The branch is here if you want to build it yourself. Otherwise, I've built the binaries for windows 10 available here. It should be as simple as unzipping the folder and running openmw-cs. You may need to install the visual studio redistributable. The SHA256 hash is 7db9728f1da917957ba0ba1274f25056b0205d479004ced72831111d3de7c7bb.

So first of all, it looks as though you are indexing your data folder twice (missed that at first). Do you need to do so? I would suggest removing either "C:\Program Files (x86)\GalaxyClient\Games\Morrowind\Data Files" or "C:\Program Files (x86)\GalaxyClient\Games\Morrowind\" from the list of data folders in your openmw.cfg. That should halve your reload times.

I'm afraid though, I cannot optimize the other issue, which is a large amount of files. Really, the only way to significantly reduce the amount of time spent doing that would be to remove it. That strategy doesn't fit so well with how the editor/game which share this same bit of code work.

Edit: Looks like scrawl beat me.
Edit 2: Remove "C:\Program Files (x86)\GalaxyClient\Games\Morrowind\". I wasn't thinking when I gave the option of either.

Having removed one data path and halving the reload time, it's become a lot more usable. It's not everyday you get a 100% speedup! It's a funny thing with the data paths though. As mentioned, I did a clean install of OpenMW and Morrowind:

C:\Program Files (x86)\GalaxyClient\Games\Morrowind is what OpenMW wizard offered me as the default data path, but neither OpenMW, the launcher, nor OpenMW-CS could run the game (morrowind.bsa missing).C:\Program Files (x86)\GalaxyClient\Games\Morrowind\Data Files is what I added and it worked, but I didn't notice it caused double loading of assets, having wrongly asumed that the other path didn't do anything, as it didn't work. Is this a bug then?

Anyway, thank you for your help on the issue, glad to have it working rather decently now.